1. Field of the Invention
This invention relates broadly to implant devices and methods used in the abdominal aorta. More particularly, this invention relates to repair devices and methods for treating abdominal aortic aneurysms.
2. State of the Art
When a blood vessel such as a vein or an artery deteriorates and/or suffers trauma, such deterioration and/or trauma may impair the blood vessel's ability to carry blood, and often creates a high risk of rupture due to the weakened blood vessel's inability to withstand internal pressures caused by blood flow and normal flexing and compression of the blood vessel. Impaired blood flow and/or a high risk of rupture may be life threatening to a patient, particularly when the weakened blood vessel is an important (e.g. large) vein or artery. For example, the main artery in a human body is the aorta, which supplies blood to all of the body's organs except the lungs. The aorta is generally described with reference to three different portions—the ascending aorta, which rises upward from the left ventricle of the heart, the aortic arch, which arches downward from the ascending aorta, and the descending aorta, which extends downward from the aortic arch through the thorax and the abdomen. The descending aorta divides into two iliac arteries which supply blood to the pelvis and lower extremities. Deterioration or trauma to the aorta may cause abnormal dilation of the wall of the aorta as it passes through the abdomen, a condition which is called an abdominal aortic aneurysm. This type of aneurysm ordinarily occurs in the portion of the aorta below the kidneys, and if left untreated, will eventually cause the wall of the aorta to rupture. Once the aorta ruptures, fatal hemorrhaging can occur very quickly. Repair of abdominal aortic aneurysms has typically required major abdominal surgery in which the diseased segment of the aorta is removed and replaced with a prosthetic device, such as a synthetic stent graft.
To repair the abdominal aortic aneurysm, the synthetic stent graft is delivered from the femoral or iliac artery to the aneurysm via a delivery catheter. The stent graft is then expanded to secure the stent graft within the aorta, and to define a passageway through the abnormally dilated section of the aorta to fluidly couple a healthy section of the aorta upstream of the aneurysm with one or more blood vessels downstream of the aneurysm. For example, if the abdominal aortic aneurysm occurs below the kidney area, then the surgeon generally must fluidly couple a portion of the aorta upstream of the aneurysm with portions of both of the iliac arteries downstream of the aneurysm to maintain bloodflow therebetween while excluding the abnormally dilated section of the aorta. The risks associated with repairing an abdominal aortic aneurysm are numerous, and the success of such procedures is dependent upon many variables, including the time required to complete the procedure, the type and quality of the stent grafts used, and the ability of the surgeon to accurately position the stent grafts in the patient.